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arXiv · 1803.07774

Measurement of Time-dependent $CP$ Asymmetries in $B^{0}\to K_S^0 ηγ$ Decays

H. Nakano·A. Ishikawa·K. Sumisawa·H. Yamamoto·I. Adachi·H. Aihara·S. Al Said·D. M. Asner·V. Aulchenko·T. Aushev·R. Ayad·V. Babu·I. Badhrees·V. Bansal·P. Behera·C. Beleno·B. Bhuyan·T. Bilka·J. Biswal·A. Bozek·M. Bracko·D. Cervenkov·V. Chekelian·B. G. Cheon·K. Chilikin·K. Cho·S. -K. Choi·Y. Choi·S. Choudhury·D. Cinabro·S. Cunliffe·N. Dash·S. Di Carlo·Z. Dolezal·S. Eidelman·J. E. Fast·T. Ferber·B. G. Fulsom·R. Garg·V. Gaur·N. Gabyshev·A. Garmash·M. Gelb·A. Giri·P. Goldenzweig·Y. Guan·E. Guido·J. Haba·T. Hara·K. Hayasaka·H. Hayashii·M. T. Hedges·S. Hirose·W. -S. Hou·T. Iijima·K. Inami·G. Inguglia·R. Itoh·M. Iwasaki·Y. Iwasaki·W. W. Jacobs·I. Jaegle·H. B. Jeon·S. Jia·Y. Jin·T. Julius·A. B. Kaliyar·G. Karyan·T. Kawasaki·C. Kiesling·D. Y. Kim·H. J. Kim·J. B. Kim·K. T. Kim·S. H. Kim·K. Kinoshita·P. Kodys·S. Korpar·D. Kotchetkov·P. Krizan·R. Kroeger·P. Krokovny·T. Kuhr·R. Kulasiri·T. Kumita·Y. -J. Kwon·J. S. Lange·I. S. Lee·S. C. Lee·L. K. Li·Y. Li·Y. B. Li·L. Li Gioi·J. Libby·D. Liventsev·M. Lubej·T. Luo·J. MacNaughton·M. Masuda·T. Matsuda
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Abstract

We report a measurement of time-dependent $CP$ violation parameters in ${B^0 \to K_S^0 ηγ}$ decays. The study is based on a data sample, containing ${772 \times 10^6 B\bar{B}}$ pairs, that was collected at the $Υ(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+ e^-$ collider. We obtain the $CP$ violation parameters of ${{\cal S} = -1.32 \pm 0.77 {\rm (stat.)} \pm 0.36{\rm (syst.)}}$ and ${{\cal A} = -0.48 \pm 0.41 {\rm (stat.)} \pm 0.07{\rm (syst.)}}$ for the invariant mass of the $K_S^0 η$ system up to 2.1 GeV/$c^2$.

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H. Nakano, A. Ishikawa, K. Sumisawa, H. Yamamoto, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, I. Badhrees, V. Bansal, P. Behera, C. Beleno, B. Bhuyan, T. Bilka, J. Biswal, A. Bozek, M. Bracko, D. Cervenkov, V. Chekelian, B. G. Cheon, K. Chilikin, K. Cho, S. -K. Choi, Y. Choi, S. Choudhury, D. Cinabro, S. Cunliffe, N. Dash, S. Di Carlo, Z. Dolezal, S. Eidelman, J. E. Fast, T. Ferber, B. G. Fulsom, R. Garg, V. Gaur, N. Gabyshev, A. Garmash, M. Gelb, A. Giri, P. Goldenzweig, Y. Guan, E. Guido, J. Haba, T. Hara, K. Hayasaka, H. Hayashii, M. T. Hedges, S. Hirose, W. -S. Hou, T. Iijima, K. Inami, G. Inguglia, R. Itoh, M. Iwasaki, Y. Iwasaki, W. W. Jacobs, I. Jaegle, H. B. Jeon, S. Jia, Y. Jin, T. Julius, A. B. Kaliyar, G. Karyan, T. Kawasaki, C. Kiesling, D. Y. Kim, H. J. Kim, J. B. Kim, K. T. Kim, S. H. Kim, K. Kinoshita, P. Kodys, S. Korpar, D. Kotchetkov, P. Krizan, R. Kroeger, P. Krokovny, T. Kuhr, R. Kulasiri, T. Kumita, Y. -J. Kwon, J. S. Lange, I. S. Lee, S. C. Lee, L. K. Li, Y. Li, Y. B. Li, L. Li Gioi, J. Libby, D. Liventsev, M. Lubej, T. Luo, J. MacNaughton, M. Masuda, T. Matsuda. 2018-04-30. Measurement of Time-dependent $CP$ Asymmetries in $B^{0}\to K_S^0 ηγ$ Decays. https://doi.org/10.1103/physrevd.97.092003

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